Global Patent Index - EP 1738839 B1

EP 1738839 B1 20090826 - Cold rolling process for metal tubes

Title (en)

Cold rolling process for metal tubes

Title (de)

Kaltwalzprozess für Metallrohre

Title (fr)

Procédé de laminage à froid pour tubes métalliques

Publication

EP 1738839 B1 20090826 (EN)

Application

EP 06253228 A 20060622

Priority

JP 2005188365 A 20050628

Abstract (en)

[origin: EP1738839A2] In the cold rolling process by pilger rolling that holds a mandrel between each of paired roll-dies, by optimizing the side relief rate SR and the pass schedule factors such as the Area Rd, ID Rd and the feed rate F of the workpiece material, and further by properly selecting the taper ¸1 in the primary deformation zone of mandrel and the taper ¸2 in the final size reduction zone thereof, the dimension-related shape characteristics (near-perfect round shape) of the tube inside surface after the final finishing rolling process by pilger rolling can be ascertained to thereby ensure excellent surface property without requiring a new apparatus, and further without causing the decrease of the product yield and/or the increase of the manufacturing costs. Thus, this can be widely applied for producing steam generator tubes which exhibits high S/N ratio in the inner coil eddy current testing.

IPC 8 full level

B21B 21/00 (2006.01)

CPC (source: EP US)

B21B 21/00 (2013.01 - EP US); B21B 21/005 (2013.01 - EP US); B21B 21/02 (2013.01 - EP US); B21B 38/00 (2013.01 - EP US)

Designated contracting state (EPC)

CZ FR SE

DOCDB simple family (publication)

EP 1738839 A2 20070103; EP 1738839 A3 20070905; EP 1738839 B1 20090826; CA 2550931 A1 20061228; CA 2550931 C 20090106; CN 100406144 C 20080730; CN 1891364 A 20070110; US 2006288750 A1 20061228; US 7197906 B2 20070403

DOCDB simple family (application)

EP 06253228 A 20060622; CA 2550931 A 20060627; CN 200610090719 A 20060628; US 47511506 A 20060627